Health Benefits of Weight Training
- Increases bone density (Hurley 1994)
- Increases glucose uptake (Hurley 1994)
- Increases gastrointestinal transit time (Koffler 1992)
- Improved HDL levels (Stone 1982, Hurley 1988)
- Reduced resting blood pressure (Harris 1987)
- effects of weight training equal to aerobic exercise (Westcott
- Reduced low back pain (Risch 1993)
- requires isolated low back strength training
- Reduced osteoarthritis and rheumatoid arthritic pain (Tufis
- Reduced depression (Signh 1997)
Men and women reach peak strength around 20 to 25 years of
age. After age 25, strength generally decreases an average of
1% per year. Therefore, a 65 year old would only have about 60%
of the strength they had at age 25. Individuals who are more
active, or those who continue to strength train, can considerably
decrease this tendency for declining muscular strength.
Strength training for older adults can reverse the loss of
muscle mass and enhance their ability to perform activities of
Welle S. Resistance training in older persons. Clinical
Geriatrics 1998;6 (1):48-59.
Radakovich J. Prescribing resistance training for elderly
patients. Your Patient and Fitness 1997;11(2):27-30.
Strength Correlates to Muscle
A muscle's strength has a strong relationship to its cross
sectional area in both men and women. Muscle enlargement with
a corresponding increase in strength was first shown scientifically
as early as 1897.
Ikai M, Fukunaga T, Calculation of muscle strength per
unit cross-sectional area of human muscle by means of ultrasonic
measurements. Int Z Angew Phsiol, 26:26-32, 1968.
Hetting T: Physiology of Strength. Springfield. Ill, C.
C Thomas, 1961.
Morpurgo B: U:ber Aktivita:ts-Hypertrophie der willkurlichen
Muskeln. Virchows Arch. Pathol Anat Physiol, 150:522-544, 1897.
Strength recovery was noted in an early exercise physiology
textbook. Elbow flexors were tested for strength and were worked
- 69% of strength was regained after 30 seconds of recovery
- 82% of strength was regained after 2.5 minutes
- 87% of strength was regained after 7.5 minutes
- 95% of strength was regained after 42.5 minutes
- only 26% more than what had been regained after a 30 second
Morehouse LE, Augustus TM (1971), Physiology of exercise,
The C.V. Mosby Company, Saint Lois, 6th Ed, pg 60.
Heavy resistance training can stimulate hypertrophy of both
Type I and II fibers, with Type II fiber experiencing the greatest
rate of hypertrophy. Also see Fiber
Gonyea & Sale 1882; Hakkinen & Komi 1985; Hakkinen,
et al 1989; MacDougall et al. 1980; Thorstensson 1976.
Combined Muscular Strength
It is estimated that if all the muscles of the human body
work together, that it could lift 11 tons, the equivalent of
Strength training increases neuromuscular efficiency
- Increased number of motor units recruited
- Increased firing rate of each motor unit
- Increased synchronization of motor unit firing
Also see Motor Development.
Resistance training incorporating high-volume, moderate-intensity,
and short rest periods, may increase capillarization in the muscles
(Schantz 1982; Tesch, et al. 1984). Bodybuilders who typically
perform this sort of training were able to exercise at a higher
percentage of their 1 rep max for 3 sets of 10 repetitions, compared
to powerlifters when plasma lactate concentrations were equally
elevated in both groups (Kreamer et al 1987).
Strength gains from a particular exercise or movement appear
to effect strength gains of other exercises for similar or even
Introduction of Weighted Chest Dips may increase strength
in Bench Press, Incline Bench Press, and Shoulder Press.
Introduction of Pullover may increase Chin-up strength. The
increased strength for Chin-ups may also, in turn, increase strength
for more remotely related exercises such as Chest Dips, Bench
Press, or Arm Curls.
Although the moments are not exactly the same, common muscles
are involved with these different movements. This phenomenon
would suggest that a particular new exercise added to a workout
may indirectly increase strength for other more commonly performed
exercises, even seemingly unrelated movements. Also see Interdependent
Strength following injuries.
Approximately 20 million women in the United States are affected
by osteoporosis, leading to multiple fractures and increased
Boning up on osteoporosis: a guide to prevention and treatment.
Washington, D.C.: National Osteoporosis Foundation, 1991.
training has been shown repeatedly to increase bone marrow density,
which can decrease the morbidity and mortality resulting from
Hamdy R., Anderson J, Whalen K, Harvill L. Regional differences
in bone density of young men involved in different exercises.
Medicine and Science in Sports and Exercise 1994; 26: 884-888.
Heinonen A, Oja P, Kannus P, Sievanen H, Manttari A, Vuori
I. Bone mineral density of female athletes in different sports.
Bone and Mineral 1993;23:1-14.
Karlson M., Johnell O. Obrant K. Bone mineral density in
weightlifters. Calcified Tissue International. 1993;52:212-215.
Nelson ME, Fiatarone MA, Morganti CM, Trice I, Greenberg
RA, Evans WJ. Effects of high intensity strength training on
multiple risk factors for osteoporotic fractures. A randomized
controlled trial. JAMA 1994;272(24):1909-1914.
Pocock NA, Eisman J, Gwinn T, Sambrook P, Kelly P, Freund
J, et al. Muscle strength, physical fitness, and weight but not
age to predict femoral neck bone mass. Journal of Bone and Mineral
Menkes A, Mazel S, Redmond RA, Koffler K, Libanati CR,
Gundberg CM, et al. Strength training increases regional bone
mineral density and bone remodeling in middle-aged and older
men. Journal of Applied Physiology 1993; 74(5):2478-2484.
Early Kinesiology Study
FE Nipher, Assistant Professor of Physics in Washington
University (1875). On the Mechanical work done by a muscle before
exhaustion. American Journal of Science and Arts. 9(100), 130-137.
This article was published in America's first scientific journal.
The journal article mentions strength adaptation, daily work
volume (kgr.-meters), dynamometer, and differentiates 'static
work' versus 'dynamic work'.
Nipher also later published a study on a form of serial
"The original dumbbell was an apparatus contrived like
that for ringing church-bells; that is, a heavy fly-wheel with
a weight attached, which was set in motion like a church-bell,
until it acquired sufficient impetus to carry the gymnast up
and down, and so bring the muscles into active play. There is
one at New College, Oxford, to the present day. The modern weights,
so called, produce similar results, in a less cumbrous and more
agreeable manner." - Edwards' Words, Facts, and Phrases.
Phyfe WHP (1901) Five Thousand Facts and Fancies, GP Putnam's
Sons, pg 250.